Question

what number must be added to each term of the ratio 7 :5 so that it becomes 4:3 ?

Answer 1

add 17 to 7 and 13 to 5 so that they become 24:18 => 4:3

Answer 2

Let the number be x

$\frac{7 + x}{5 + x} = \frac{4}{3} \\ \\ 3(7 + x) = 4(5 + x) \\ \\ 21 + 3x = 20 + 4x \\ \\ 21 - 20 = 4x - 3x \\ \\ 1 = x$
Ans. 1 is added to both the terms